This invention relates to an improved vacuum cleaning apparatus or appliance, and in particular to a portable domestic appliance of the kind described in my U.S. patent application Ser. No. 452,917. This U.S. application corresponds to European patent application No. 81302726.5.
U.S. patent application Ser. No. 452,917 describes a vacuum cleaning appliance comprising a generally cylindrical outer cyclone with an inlet for dirty air and concentrically within the outer cyclone an inner cyclone, a passageway being provided to allow air from the outer cyclone to enter an upper end of the inner cyclone. Clean air can then be withdrawn centrally from the inner cyclone and then exhausted. A related two cyclone appliance is shown in my U.S. Pat. No. 4,377,882.
The appliance of U.S. patent application Ser. No. 452,917 and U.S. Pat. No. 4,377,882 is adapted for use in two different modes: in the first mode dirt laden air enters the appliance via a ground engaging cleaning head which is attached to part of the lower end of the cleaner's casing and incorporates an elongate axially rotatable brushing member in the cleaning head; and in the second, pure section mode, dirt laden air enters the appliance through a pipe in a hose section, which may be connected to other suction tools, without the use of a rotatable brushing member.
The problem is to provide an efficient valving means for shifting between the two modes so that the modes operate separately from each other.